After we updated a new security certificate on our Exchange 2003 server our users have been unable to send messages to people they had already been sending to.
Any ideas on why this is happening?

They are getting these messages:

Subject: Undeliverable: subject

Delivery has failed to these
recipients or distribution lists:

xxx@yyy.com An error occurred while
trying to deliver this message to the
recipient's e-mail address. Microsoft
Exchange will not try to redeliver
this message for you. Please try
resending this message, or provide the
following diagnostic text to your
system administrator.

The following organization rejected
your message: yyy.com.

EDIT - SOLUTION

It was a setting on our send connector in exchange. It wasn't changed when the new SSL certificate was added. The reverse DNS lookups on our email weren't matching the old setting

1 Answer
1

It may be a complete coincidence that this has started happening since your certificate update as it certainly seems unrelated.

It is often the case that having many hyperlinks within e-mails can cause this problem due to issues with Spam/Virus filter configuration at your ISP. I suggest you try sending a simple "hello world" e-mail to the same recipient to see if that gets through

If that also doesn't work then it might be that your signature contains links that your ISP doesn't like so also try to remove those also.

If that still fails, I suggest you get in touch with the helpdesk of the people who are giving you the error, in this case carrierzone.com

It was a setting on our send connector in exchange. It wasn't changed when the new SSL certificate was added. The reverse DNS lookups on our email weren't matching the old setting.
–
TonyApr 18 '11 at 19:49

Maybe I missed something but I don't know how your answer applies to this question. Why would hyperlinks in emails start causing issues when the last major change was the Cert? I also don't know how your ISP would have anything to do with the hyperlinks contained in the emails. It looks like you did a google search on the reason for rejection and just assumed that was the same issue.
–
CheekaleakApr 18 '11 at 19:59